Moreover, IFN-α treatment induces the expression of programmed cell death-1 (PD-1) on tumor-infiltrating T cells and PD-L1 on tumors [13], which can be neutralized using checkpoint blockade with anti-PD-1/PD-L1 mAbs [14, 15], currently in clinical trials in both lymphoma and MM. The gene discussed is PDCD1; the disease is neoplasm.